Heating tube



F. W. OFELDT HEATING TUBE Filed June 50, 1936 ATTORNEY.

Patented Mar. l5,

I uNiTEofs'rA-TEs' j PA FFICE I sums -nas-rmarunn @r ew. 01cm. macaw-c; Pa, assignor to Homestead Valve Manufacturing Company, g Coraopoiis, Pal, a corporation oi Pennsylvania I AppllcationJune 30,:l936;Sei-lfl No. 88.100

e (or. 122-250) This invention relates generally to heating tube structure and more particularly to heating tubes The present practice in the design of heating coils has been directed largely to the formation of the coils to provide a bafliing and a flue eflect at the proper positionswithin the combustion chamber. Other designshave been produced to prevent excessive condensation within the come bustion chamber by arranging the heating coil to ing from the coil. This has-beena'ccomplished by feeding the fluid in a coil that leads fromthe top of the heater and circulates around the cooler portions of the combustion chamber before it becomes exposed to the highly heated portions. Again the coils are sometimes wound around the shell formingthe combustion chamber. so that .the fluid therein may be preheated before it is circulated over or through the combustion chamber. Heating coils are frequently provided with radiating flns for increasing their eflective heat therein collects at the top of the coil which forms a single chamber, which may be compared to that of a steam boiler.

The principal-object of this invention is the provision of aheating coil that, while having the advantages of the present art, is designed to provide a multiplicity of traps within the coil to prevent the vapor or steam from collecting in the upper portion when the fluid is not continuously traveling through the coil.

This arrangement prevents the discharge of a considerable quantity of vapor or steam from the heating coil when it is intermittently started but permits the discharge of a blend of the fluid in the form of a vapor or steam with the liquid of the fluid when the flow is reestablished.

' This is especially advantageous where the fluid comprises an emulsion of different fluids'which, owing to their inherent characteristics, may segregate if permitted to stand. a short While,

I coils of this character the vapor or steam formed Another object of this invention resides in the manner in which the heating coils are positioned with respect to the burner. V

This invention also includes the provision of a novel form 01' heating coil. supporting. means within the combustion chamber. p

Another object is the provision of.- a novel ar rangement of aplurality of heating coils within thecombustion chamber which effects an in-. creasing capacity. through the heating coils, to permit expansion of the fluid as it proceeds therethrough. I

Other objectsandadvantages appear liereinj after. t c y.

In the accompanying drawing I have illustrated a practical embodiment of, the pginciples oi my inventionr i Fig. 1 is a side elevation of a plurality of heating coils within a combustion chamberand showing diagrammatically an arrangement oi a burner having associated apparatus,.parts of which are 20 broken away, disposed ,in proper relation with respect to the heating coils. I

Fig. 2 is a front elevation of a heating coil having a portion of the front passes of the. coilturns shown in section. a 4 v Fig. 3 isa frontelevation showing apart of a heating coil with some- 01 the front passes cut away and the rear passes of a few coil turns being in section. a I

Fig. 4 is a plan view showing a modification of a heatingcoil arrangement wherein three coils are employed. p

Referring to the drawing, Ill represents a combustion chamber supported on the base ring Il I2 represents aheating coil formed in the shape of a helix from any suitable tubing. The upper end 01' the coil l2-is connected to one port of the. junction block or fitting l3. it represents a second heating coil, the upper end oi which is 40 connected to another port in the block Hi, thereby forming' a continuous passageway from .the lower end of the coil'l2 through theblock l3 to the lower end of the coil M. 1

The lower end of the coil I2 is arranged'to be connected to a source of fluid supply. not shown. The fluid supply may be from a single source or from separate sources. The pipe lines i5 and I6 represent the connections between separate. sources of fluid supply and the fluid pumping chambers I1 and I8 respectively of the displacementpump Ill. The separate fluids may then be joined by a commondischarge passage within the pump casing head. The fluid blend. thus formed is pumped through the pipe 20, the check l2, thence up through the coil l2, the block l3, and down through the coil l4, to the discharge line 23. The end of the discharge line may be provided with a suitable dispensing nozzle and/or valve depending upon the character of the use to J emulsion of the steam'or vapor with the liquid 'would'be "formed immediately by'reason of the which the heater is applied.

24 represents a pipe line from a source of fuel supply which isdirected to the pump chamber 24 in the pump is from whence it travels through the pipe 26, the metering valve 21, the pipe line 28 to the fuel heating coil 29, where it may be vaporized before it is delivered to the nozzle 32. 3| represents a priming tray for the nozzle 22.

The displacement pump I! may be of the type disclosed in my application for I etttersPatent Serial No. 87,847, filed June 29, 1936.v The burner structure may be of the character disclosed in my application for Letters Patent Serial No. 91,405"

flied July 18, 1936.

, 32 represents a gauge in the fuel line 22 for indicating the pressure therein. 33 represents a pressure indicating gauge in the discharge line 23 of the heater. 34 represents a control line connected to the discharge line 23 for transmitting temperature and/or pressure intelligence to the controller 35, which accordingly operates the pump motor 36 through the contactor 21.

As disclosed above, the heating coils l2 and i4 may bewound in the form of a helix. However, when they are mounted within the combustion chamber they shouldbe disposed at anangle so that the lowest portion of each coil turn is below the juncture between the'next adjacent coil turns thereabove and therebelow. This is illustrated in the drawing wherein the front passes of the coil turns are shown in section in Fig. 2 and the rearpasses 39 of the coil turns are shown in section in Fig. 3. Each of thesevlews demonstrate that the lowermost portion 40 of each coil turn is filled with liquid as indicated at 4| and the up permost portion or the juncture between each coil turn is fllled with steam or vapor of the liquid as indicated at 42.

Thus each turn of the heater coils represents a small boiler when the fluid is not flowing through the coil. This condition is set up within the heating coils when the discharge through the pipe 23 is stopped or throttled sumcientlyto permit an increase in pressure at the discharge of the heater. This intelligence is transmitted through 34 to the controller 35, which may select through the contactor 31 to stop or reduce the speed of the pump motor and thereby stop or reduce the flow of fluid and its proportionate amount of fuel which decreases the pressure.

If the temperature of the emulsion in the discharge pipe 23 is excessive, the controller 35 will operate the contactor 31 to stop or reduce the flow of fuel and fluid to the heating coil.

If the flow of the fluid emulsion is reduced or stopped within the heating coils sufficiently to permit the emulsion to separate into steam or vapor and the-"liquid as indicated; and subsequently the flow is reestablished or increased, an

series'of trapszh This would not be true if the ste'am'-or= vapor of the system were permitted to collect in one large body within the heater as in z-tliecase of an ordinary steam boiler.

By controlling the metering of the fluid and the fuel and with the provision of these traps, I am enabled to maintain the proper consistency of the parts forming the emulsion. Thus I may Y valve 2|, the pipe 22 to the lower end of the coil produce a mixture of a liquid and saturated steam or vapor or steam and vapor of a liquid in proper proportions. These results can not be obtained by the conventional steam boiler, or the like.

Referring to Fig. 4, 42 represents the lead heating coil connected to the pipe 22 as shown at 44. The upper end of the coil 42 is connected to the three-way block or fitting 45, which in turn is connected to the upper end of the coils 46 and 41. The lower end of the coil 46 is connected at 48 to the pipe 40 which traverses the bottom of the combustion chamber and is connected to the lower end of coil 41 as shown at lil, and passes thence to the discharge pipe 22.

, Thus the fluid travels up the coil 42 where it separates and travels down the coils 4i and 41.

As the fluid travels up the coil 43 it is being heated and therefore expands and the return coils 46 and 41 provide the additional space to compensate for such expansion. When two coils are employed as illustrated in Fig. 1 the return coil l4 may be formed with tubing having a larger internal opening than that of coil 12 to provide for the expansion of the fluid. This disclosure is similar to that shown and described in my Patent No. 1,925,643, issued September 5, 1933.

It should be noted that the coils 42, 46 and 41 are each tilted to an angle that will provide a trap in each coil turn as illustrated in Figs. 2 and 3.

To stiffen the coils andmaintain their coil turns in proper spaced relation it is convenient to provide the bracing members 5| which are secured at their lower ends to the base ring II and extend along the perimetral surface of the coil turns. It may be found necessary to secure only the top coil turn to the brace 5|, as indicated at 52. The coil turns may be secured to the brace as by strapping, silver-soldering, welding or other suitable means. Again additional support may be given to the coils by suspending the blocks l3 and 45 from the upper part of the combustion chamber as indicated at 53 in Fig. 1.

The size of the tubing opening and the diameter of the helical heating coils are the material dimensions for determining the pitch that these coils must assume to provide a series of traps therethrough. The helical coil is unquestionably the simplest and most economical to manufacture. However, a series of traps could be formed by bending the tubing in corrugated waves as the coil is being wound and it would not be required to have a batter to produce the traps. Again I may employ a series of horizontal tubes having traps intermediate of their ends. These tubes may terminate in headers to provide multiple passes across the combustion chamber.

As a preferred form I have shown and described a helical coil arranged within the com-' bustion chamber to permit each spaced coil turn to function as a trap. The angular disposition of these helical coils within the combustion ,chamber prevents the flame from traveling in a characteristics of both. The gaseous substance is frequently referred to as wet or saturated steam but it may include vapors of soluble substances derived from the solution fed to the heating coils.

I claim:-

1. In apparatus for producing a spray composed of a mixture of a liquid, a vapor of a liquid and steam of a liquid, the combination of a tube, means for supplying a predetermined amount of liquid to said tube, means for supplying fuel to said tube for heating said liquid at a rate so correlated with the rate of supplying liquid as to produce a predetermined ratio be-- tween the elements of the mixture, and a plurality of traps arranged along said tube for collecting relatively small portions of the mixture during the stoppage or retardation of the travel of the liquid to prevent a material segregation of the elements of the mixture.

2. In apparatus for producing a spray composed of a mixture of a liquid, a vapor of a liquid and steam of a liquid, the combination of an inclined tube, means for supplying a prede- Q termined amount of liquid to said tube, means for supplying fuel to said tube for heating said liquid at a rate so correlated with the rate of supplying liquid as to produce a predetermined ratio between the elements of the mixture, and

aplurality of traps arranged along said tube for collecting relatively small portions .of the mixture during the stoppage or retardation of the travel of the liquid to prevent a material segregation of the elements of the mixture.

3. In apparatus for producing a spray composed of a mixture of a liquid, a vapor of a liquid and steam of a liquid, the combination of a helical tube, means for supplying a predetermined amount of liquid to said tube, means for supplying fuel to said tube for heating said liquid at a rate so correlated with the rate of supplying liquid as to produce a predetermined ratio between the elements of the mixture, and a plurality-of traps arranged along said tube for collecting relatively small portions of the mixture during the stoppa e or retardation of the travel of the liquid to prevent a material segregation of the elements of the mixture.

4. In apparatus for producing a spray composed of a mixture of a liquid, a vapor of a liquid and steam of a liquid, the combination of a helical tube, means for supplying a predetermined amount of liquid to said tube, means for supplying fuel to said tube for heating said liquid at a rate so correlated with the rate of supplying liquid as to produce a predetermined ratio between the elements of the mixture, said helical tube being disposed at an angle to the vertical to trap relatively small portions of the mixture during the stoppage orretardation of the travel of the liquid to prevent segregation of the elements' of the mixture.

5. In apparatus for producing a spray composed of a mixture of a liquid, a vapor of a liquid and steam of a liquid, the combination of a. plurality of helical heating coils, means for supplying a predetermined amount of liquid to said coils, means for supplying fuel to said coils for heating said liquid at a. rate so correlated with the rate of supplying liquid as to produce a predetermined ratio between the elements of the mixture, and the axes of said coils be n disposed on non-intersecting inclined axes to provide a plurality of traps for collecting relatively 6. In apparatus for producing a spray composed of a mixture of a liquid, a vapor of a liquid and steam of a liquid, the combination of a tube, means for supplying a predetermined amount of liquid to said tube, means for supplying fuel to said'tube for heating said liquid at a rate so correlated with the rate of supplying liquid as to produce a predetermined ratio between the elements of the mixture, means actuated by the temperature of the mixture prior to its discharge as a spray for simultaneously stopping and startingthe supply of liquid and fuel to said tube, and a plurality of traps in said tube for segregating relatively small portions of the mixture when its movement is retarded or stopped within thetube. 

